Mycoestrogens Influence Development

Exposure to mycoestrogens appears to affect the body size and breast development of girls, according to a study from NIEHS-supported researchers. It is important to understand how mycoestrogens influence the development of girls because it could have implications for their future breast cancer risk.

The researchers looked at zearalenone and zeranol mycoestrogens, which are commonly found in the food supply. Zearalenone is a fungal product that can be found in grains and plant foods consumed by livestock or humans, and zeranol is sometimes used to enhance meat production. They studied 163 healthy girls (ages nine and ten) participating in the Jersey Girl Study, which is examining factors affecting the onset of puberty in girls.

The mycoestrogens were detected in the urine of 78 percent of the participants, and girls tended to be shorter and less likely to have reached the onset of breast development if urinary mycoestrogens were detected. Preliminary analysis associated intake of beef and popcorn with urinary mycoestrogens. The results point to the need for more research to fully understand the effects of mycoestrogens on development.